Computer Security Midterm Segment 2 | AES Algorithm, Cryptanalysis, Stream & Block Cipher

🔐 *Computer Security Midterm Preparation | Segment 2 | AES Algorithm, Cryptanalysis, Stream Cipher & Block Cipher* Welcome to *Just A Random Engineer!* 🚀 In this lecture, we cover **Computer Security Segment 2**, focusing on the Advanced Encryption Standard (AES), AES Encryption Operations, Key Expansion, Cryptanalysis of Substitution and Transposition Ciphers, and the differences between Stream Ciphers and Block Ciphers. This video provides step-by-step explanations, mathematical calculations, practical examples, and exam-focused solutions to help CSE students prepare for their Computer Security Midterm Examination. 📚 *TOPICS COVERED IN THIS VIDEO* 🔹 *1. Advanced Encryption Standard (AES) Algorithm* ✅ Introduction to AES ✅ AES as a Symmetric Block Cipher ✅ AES Block Size and Key Sizes ✅ AES-128, AES-192, and AES-256 ✅ Number of Rounds in AES ✅ AES Encryption Process ✅ AES State Matrix Representation ✅ Complete AES Algorithm Step by Step 🔹 *2. AES Encryption Operations* ✅ SubBytes Transformation ✅ ShiftRows Transformation ✅ MixColumns Transformation ✅ AddRoundKey Transformation ✅ Initial Round, Main Rounds, and Final Round ✅ Step-by-Step AES Mathematical Operations 🔹 *3. AES SubBytes Transformation* ✅ Introduction to AES S-Box ✅ Substitution Using the S-Box Table ✅ Row and Column Selection ✅ Hexadecimal Representation ✅ Step-by-Step SubBytes Examples 🔹 *4. AES ShiftRows Transformation* ✅ Introduction to ShiftRows ✅ Row-Wise Circular Left Shifting ✅ First, Second, Third, and Fourth Row Operations ✅ Step-by-Step Matrix Transformation 🔹 *5. AES MixColumns Transformation* ✅ Introduction to MixColumns ✅ Matrix Multiplication in GF(2⁸) ✅ Multiplication by 01, 02, and 03 ✅ XOR Operations in AES ✅ Polynomial Reduction Using 0x1B ✅ Step-by-Step MixColumns Calculations 🔹 *6. AES AddRoundKey Transformation* ✅ Introduction to AddRoundKey ✅ XOR Between State and Round Key ✅ Hexadecimal XOR Operations ✅ Step-by-Step AddRoundKey Examples 🔹 *7. AES Key Expansion and Round Constants* ✅ Introduction to AES Key Scheduling ✅ Original Key Matrix ✅ Key Expansion Process ✅ RotWord Operation ✅ SubWord Operation ✅ Round Constant (Rcon) ✅ XOR Operations During Key Expansion ✅ Generating AES Round Keys 🔹 *8. Cryptanalysis of Substitution Cipher* ✅ Introduction to Cryptanalysis ✅ Substitution Cipher Cryptanalysis ✅ Frequency Analysis ✅ Identifying Letter Patterns ✅ Weaknesses of Classical Substitution Ciphers ✅ Techniques for Recovering Plaintext 🔹 *9. Cryptanalysis of Transposition Cipher* ✅ Introduction to Transposition Cryptanalysis ✅ Understanding Character Rearrangement ✅ Letter Frequency Preservation ✅ Analyzing Columnar Transposition ✅ Identifying Possible Key Lengths ✅ Recovering Plaintext from Ciphertext 🔹 *10. Stream Cipher and Block Cipher* ✅ Introduction to Stream Cipher ✅ Introduction to Block Cipher ✅ Working Principles of Both Ciphers ✅ Bit-by-Bit and Block-by-Block Encryption ✅ Key Differences Between Stream and Block Ciphers ✅ Examples and Applications ✅ Comparison for Midterm Examination 🎯 *WHAT YOU WILL LEARN* By the end of this lecture, you will understand: ✔ How AES Encryption Works Step by Step ✔ How to Perform SubBytes and ShiftRows ✔ How to Calculate MixColumns Using GF(2⁸) ✔ How AddRoundKey Uses XOR Operations ✔ How AES Round Keys Are Generated ✔ How RotWord, SubWord, and Rcon Work ✔ How to Perform Cryptanalysis of Classical Ciphers ✔ How Stream Ciphers Differ from Block Ciphers ✔ How to Solve Important AES Mathematical Problems 🎓 *WHO SHOULD WATCH THIS VIDEO?* 📌 Computer Science and Engineering Students 📌 Computer Security Students 📌 Cybersecurity and Cryptography Learners 📌 Students Learning AES Encryption 📌 University Midterm and Final Exam Candidates 💡 *WHY IS THIS LECTURE IMPORTANT?* AES is one of the most widely used symmetric encryption standards in modern cryptography. Understanding its mathematical operations, finite field arithmetic, and key expansion process is essential for Computer Security students. This lecture simplifies AES calculations and cryptanalysis concepts through structured explanations and exam-oriented problem-solving. 📢 *ABOUT JUST A RANDOM ENGINEER* Just A Random Engineer is an educational YouTube channel dedicated to simplifying Computer Science and Engineering concepts through detailed tutorials, mathematical solutions, and examination-focused lectures. 🔗 *SUBSCRIBE TO JUST A RANDOM ENGINEER:*    / @hasnain_nabil   👍 Like the video if you find it helpful. 💬 Comment your questions below. 📤 Share this lecture with your classmates. 🔔 Subscribe for more Computer Security tutorials! *#ComputerSecurity #AESAlgorithm #AESEncryption #Cryptanalysis #SubBytes #ShiftRows #MixColumns #AddRoundKey #AESKeyExpansion #StreamCipher #BlockCipher #Cryptography #CyberSecurity #ComputerSecurityMidterm #JustARandomEngineer*